Document 6577765

Aug. 23, 1960
D. H. STAELIN
2,949,707
METHOD AND APPARATUS FOR GRINDING AND POLISHING SHEET GLASS
Filed Feb. 23,.1956
2 Sheets-Sheet 1
INVENTOR.
DA V/D H. STAEL/N
A TTORNEYS
Aug- 23, 1960
D. H. STAELIN
_
2,949,707
METHOD AND APPARATUS FOR GRINDING AND POLISHING SHEET GLASS
Filed Feb. 23, 1956
2 Sheets-Sheet 2
,
//
:4
3a
n (I719 20 rtjea 3/30\F'FY
“ if
x
? 1/5
'
.
21.1%
V
7% M28
W
F2
?
"9 [/6 Fl 5.10-
(as
I 9
INVENTOR.
04 W0 H. STAEL/N
A Tram/531s‘
,
lice
2,949,77
Patented Augean, teen
2
In a ?nal stage a minimum of material is removed and
the glass surface is caused to ?ow into a polished form
under limited pressure by a form of gentle horizontal
2,949,707
rubbing with high frequency transducer means.
METHOD AND APPARATUS FOR GRINDING v
- Other objects and features of the invention will ap
pear as the description progresses. Referring now to
AND POLISHING SHEET GLASS
the drawings:
David H. Staelin, 2385 Evergreen Road,
Ottawa Hills, Ohio
Filed Feb. 23, 1956, Ser. No. 567,122
11 Claims. (Cl. ‘51-—60)
Figure 1 is a view in perspective of a section of a
- conveyor line for grinding-polishing a continuous ribbon
of glass showing an arrangement of apparatus for treat
ing the glass in accordance with the principles of the
present invention;
Figure 2 is a somewhat schematic side-elevational view
This invention relates to a method and apparatus for a
grinding and polishing ?at glass on a continuous produc
tion line basis and in particular to a method and appa
ratus adaptable to simultaneous and continuous grinding
polishing of two faces of a continuous ribbon or sheet
of glass.
It is a principal object of the invention to provide more
Figure 4 is an elevational view partially in cross sec
Figure 5 is another view in perspective of a different
type of transducer head in which abrasive-containing
?uids may be introduced directly and continuously under
grinding and/or polishing ?at glass surfaces with pre
cision On a continuous basis with a minimum of manual
Considerable progress has occurred in recent years in
the arts related to the working, cutting and drilling of
hard materials to produce desired shapes. One area in
which advancements have been made to a tremendous
extent lies in the ?eld of application of electrical trans
ducers and more particularly high frequency electrome
,
Figure 3 is an enlarged view in perspective of a type
of working head utilized to perform functions in accord
ance with the principles of the present invention;
tion of an edge-polishing head adapted for use according
'20 to the present invention;
economical and a more effective method and means for
labor.
of the apparatus and method of Figure 1;
25
the working surface thereof;
Figure 6 is a View in perspective of still another trans
ducer head of the present invention in which a plurality
of cavities within the working surface are provided for
introduction of abrasive-containing ?uids between the
working surface of the head and the surface to be worked;
Figure 7 is another arrangement of apparatus for
treating surfaces of ?at glass in accordance with this
chanical transducers for such purposes. As an example,
invention;
the use of the principles of cavitation in conjunction with
Figures 8 and 9 are somewhat schematic side-eleva
high frequency electromechanical transducers has en~
tional views showing details and two operational posi
abled chipping and cutting of hard materials such 'as 35 tions for the working head of the apparatus in Figure 7;
diamonds with much greater ease than heretofore pos
and
sible and has enabled the contouring of such materials
Figure 10 is a somewhat schematic side-elevational
to forms heretofore never obtainable. It is a purpose
view of the arrangement of apparatus utilized in accord
of the present invention to apply high frequency trans
ance with the present invention illustrating the manner in
ducer apparatus and the principles of cavitation in the
which opposite surfaces of a single ?at ribbon, plate or
art of polishing ?at surfaces of glass in the form of con
sheet of glass may be worked simultaneously in a grind
tinuous plates, sheets or ribbons.
Conventional methods of grinding and polishing glass
surfaces usually involve application of abrasive action
with disc-type apparatus having considerable limitation
from the standpoint of cumbersomeness and adaptability
to continuous production operations. The present inven
tion, however, eliminates the need for rotary disc appa
ratus and provides a ?exible method and means of
ing-polishing operation.
Turning to the drawings in greater detail, Figure 1
shows a three-stage grinding-polishing operation in each
45 stage of which a plurality of electromechanical trans
ducers are utilized to vibrate a working head as the glass
being worked is advanced continuously under the head.
In each stage of the grinding-polishing operation, the
working head extends across the continuous glass sheet
grinding and polishing glass surfaces by agitation of
15 transversely to the direction of motion of the sheet
abrasive material in liquid suspension by means of elec_ 50 and
is pressed against the surface to be treated while
tromechanical transducer heads. The transducer equip
- a suspension of ?nely divided abrasive in an appropriate
ment is operated in the frequency range of about 400
liquid is introduced under the head onto the glass surface
cycles per minute and above, in other words, in the
being worked. The amplitude of vibration of each of
range where the rate of agitation or working of the sur
the heads at the high frequencies employed is relatively
face is such that the amplitude of the transducers need 55 small, being in the order of less than .05 inch and
only be in the magnitude of a thousandth of an inch to
usually smaller than this magnitude. The amplitude is
effect removal of material. It has been found that
so small and the frequencies so high that movement of
transducer heads when used in conjunction with liquid
the working heads is not visible, but under the light con
suspended abrasives and when operated in high fre
tinuous pressure applied, material is continuously re
quency ranges have tremendous surface cutting effects
moved.
'
on surfaces toward which the heads are intimately di
In Figure 1 the apparatus is arranged to remove the
rected since the abrasive material itself acts directly on
greatest amount of material from the sheet glass ad
the surface from which the material is removed and
vanced thereunder in the ?rst stage Where the surface
acts, in a sense, to chip away the material rather than
65 vbeing worked is the roughest. Progressively less mate
abrade it.
rial is removed from the surface being treated in the
By the present description, the invention involving sur
second
and last stages of’ the grinding-polishing opera
face removal of material is exempli?ed by a process
tion.
>
which is, in a sense, a three-stage method where the
In
the
?rst
stage,
the
working
head
10
is
arranged
to
surface is ?rst preworked or chipped to eifect a pre?atten
be vibrated in a vertical direction by a plurality of trans
70
ing of the surfaces, whereafter an intermediate stage of
ducer heads 12 supported in a framework 16. The heads
working to a lesser degree of material removal is effected.
- 12 are so mounted in the housing or framework 16
2,949,707
3
that the working head 10 in addition to being vibratable
in a vertical direction, can be oscillated in a horizontal
direction by a pair of laterally disposed electromechani
cal transducers 14 ‘disposed on Opposite ends of the work
ing head 10. The latter move the head 10 and the
4i
the transducers 14 is arranged to be variable in frequency
to permit synchronization of the transverse horizontal
frequency of vibration of the head 12 to its vibration in
the vertical plane. If desired, however, the horizontal
frequency of vibration by the transducers 14 may be dif
ferent from the vibration generated by the heads 12 to
assembly of transducers 12 by way of a mechanical tie
provide a wide ‘range of motions of the head 10 in the
in structure 13 which is slidably mounted in'the frame
vertical plane transverse to the sheet 15. For example,
work 16 to permit the head 10 to be moved in. a hori
motions in the Vertical plane may correspond to a wide
zontal direction transverse to the direction of motion of
the sheet material 15 carried on the conveyor 17‘. Means 10 variety of Lissajous ?gures such as a ?gure either or el
lipses may be imparted to the head iii, if desired. In this
such as “T” rack members 19 below the conveyor pro
respect, it should be noted that as these complex motions
vide support for the conveyor belt to assure positive
level positioning of the glass sheet 15 upon passage under t are imparted to the head 16* Within a vertical plane to
effect a grinding of the surface of the sheet 15, the sheet
the heads in each stage of the operation.
<
The ?nely divided abrasive actuated by the head this 15 is being continually advanced ‘under the head 10. For
this reason, the motions imparted to the particles driven
introduced to the face of the glass sheet 15 just behind
against the surface by the head 10 are extremely com
the head 10 by way of a supply tube 11 extending across
plex but trajectories vmay be varied over a wide range to
the width and just above the sheet 15. The tube 11 is
produce any of a range of prepolished conditions ap
provided with a series of apertures arranged to effect an
proaching smoot'ncning of the surface from a rough sur
even distribution of the abrasive material across the
face condition.
width of the sheet to be carried under the head 10 by mo
Ths apparatus arrangement for surface treatment of
tion of the sheet 15 in a direction under the head. As
the sheet 15 in the second stage of grinding and polish
may be seen more clearly in Figure 2, the ?nely divided
ing includes a plurality of transducers 22 operated in
abrasive after being carried under the head 10 is sub
stantially all removed on the forward edge of the head 25 unison in a manner similar to that of the ?rst stage but
are so associated with the head 20 of this stage that they
19 by a suction tube 13 (Figure 2) to provide a rela—
drive the head in a direction diagonal to the surface of
tively clean surface for subsequent treament by the sec
the
sheet. As in the ?rst stage, the transducers are tied
and stage.
Figure 2 illustrates somewhat schematically the general
over-all picture of the grinding-polishing operation and
the apparatus utilized to effect such operation in the man
ner of Figure 1. This illustration shows the general
location of the abrasive supply tubes 11, 21 and 31 with
the heads 10, 2t) and 30, respectively, and also the
abrasive removal apparatus consisting of suction tubes
18, 23 and 38, respectively, which pick up the abrasive
particles after use in each stage. The used abrasive par
ticles recirculated in each stage for recirculation to the
supply tubes in their respective stages, if desired.
It is believed that the working of the surface for re
moval of material therefrom is effected by the abrasive
in liquid suspension and not by the tool. Since it is be
lieved that the principle of cavitation is involved in this
:highly effective process of removing material, the liquid
together structurally to permit horizontal oscillation of
30 the head 20 back and forth across the sheet 15.
The
transducer assembly and tie-in structure 23 is slidably
mounted within the frame structure 26 so that the head
20 may be reciprocated in its horizontal direction while
being dirven diagonally by the transducers 22. By rea-_
son of the fact that the head 29 is driven diagonally into
the surface of the sheet, the full amplitude of vibration
effected by the transducers 22 is diminished in a vertical
direction and dependent upon the angle at which oscil
lation occurs with respect to the sheet surface. The
smaller the angle of vibration with respect to the hori
zontal, the greater is the horizonal component of vibra
tion and the smaller is the vertical component of vibra
tion. Accordingly, for a given amplitude of vibration of
the transducers and the head 20, a range of vertical com
in which the abrasives are suspended should be selected 45 ponents can be provided from which an optimum vertical
amplitude may be selected to provide a second degree of
from among those readily subject to cavitation such as
grinding closer to a polish than is provided by the ?rst
water. It appears that the constant motion of the abra
sive particles against the face of the glass sheet being
worked results in each minute portion of the surface be
stage of the grinding-polishing operation. The abrasive
particles for the second stage of the grinding-polishing
ing impacted by abrasive particles. At the high fre 50 operation are provided by a supply tube 21 which drops
quencies desirably employed, the acceleration energy im
the particles in liquid suspension on the surface of the
parted to the liquid suspended abrasive particles is of
sheet 15 immediately before the head 20, and after use
such great magnitude that it appears that the particles
the particles and liquid are picked up by means such as
actually effect a chipping or cutting away of minute
an arrangement of a suction tube 25% immediately behind
particles of the surface. The working head 10 is made of 55 the head 20. By reason of the fact that the sheet 15 is
tough material which is not of brittle character such as
being advanced horizontally under the head 20 as the
malleable metal. The abrasive introduced thereunder
head is vibrated in a direction with a backward hori
from the supply tube 11 may be supplied in a water sus
zontal component of motion, a somewhat rotary ?owing
pension and after being used may be removed from the
or couple action is exerted upon abrasives on the surface
sheet surface by suction means such as a suction tube 60 of the-sheet by the head 20 and sheet 15 as the vertical
18 from which it can be recirculated back to the supply
component drives the abrasive particles into the sheet
tube 11.
.
15. The vertical component of vibration is proportional
In vibrating vertically the working head 10, in a sense,
to
the sine of the angle of vibration of the head 20 while
causes a digging into the surface of the sheet 15 by be
ing supported from and driven by transducers mounted 65 the horizontal component thereof is proportional to the
cosine of such angle.
at a given level above the surface within the framework
After being subjected to the ?rst and second stages
16. Since the ‘amplitude of vibration is ?xed at an ex
' of the ‘grinding-polishing operation, the surface of the
sheet 15 has been pretreated to a su?icient degree to per
small in the order of approximately .05 inch or less.
mit
a ?nal polishing of the surface. This may be ac
70
tremely small value, the digging action is correspondingly
With such a vertical chipping away of the sheet 15, the
roughest spots in such surface are ground away. Sub
sequent to such treatment, the surface is more uniform
in character and in effect pretreated for subsequent more
complished in the third stage of the grinding-polishing
operation wherein the working head 30 is oscillated in
two directions within the horizontal plane by two co
operating sets of transducers 32 and 34. The transducers‘
re?ned polishing operations.
The hcrizantal movement of the Working head 11) by 75 32 operate in unison to vibrate the head 30 in a horizontal
2,949,707
direction parallel to the {direction of advancement of the
sheet 135 on the conveyor 17.
An assembly structure 33 ‘ties the transducers 32 to
gether as a group within a support frame structure 36
and is actuated by the pair of transducers 34 located on
opposite sides of the support structure 36 to reciprocate
the head 30 in a direction transverse to the direction of
motion of the sheet 15. It will ‘be recognized that by
reason of the fact that the head 30 is movable in a for
ward and backward direction as well as a transverse di
rection, it can be imparted a circular or elliptical motion,
or may ‘be imparted other motions of non-linear form
such as that which will outline a ?gure eight or a quadru~
ple looped con?guration depending on the relationship
6
optimum of operating conditions due to pressure of the
heads against the surface of the sheet 15.
Figure 4 illustrates still another type of working head
50 which may be used more particularly to polish and
shape the edges of a sheet of glass. This head is adapted
for vibration by a transducer actuated member 53 which
moves the head in a horizontal direction generally paral
lel_ to the rough edge of the sheet to be worked. The
head has an under surface ‘consisting of two generally
horizontal ?at positions 52 and 53 having a bridging or
connecting surface portion 51 therebetween. The surface
51 extending between the vertically spaced surfaces 52
and 53 may be substantially vertical to impart a square
edge to the sheet 55, as illustrated, but it will be under
of the frequencies of vibration of the transducers 32 and 15
si'ood that various shapes may be given to the under side
34.
or working surfaces of the head such as by Way of ex
The pressure of the head 30 on the surface of the sheet
ample, shapes which will provide beveled or curved edges
15 is made adjustable by way of a variable compression
for the glass sheet.
‘
spring 38 which bears against the top of the head 30 and
Abrasive
particles
in
liquid
suspension
may be intro
is capable of being adjusted for various degrees of com 20
duced under the head 50 by providing a raised rearward
pression against the head by means of a set screw 39
edge as in the manner of the structure in Figure 3 which
The abrasive particles in liquid suspension introduced
will permit introduction of abrasive particles under the
under the head 39 are supplied from a tube 31 extend
head by being carried forward by the advancement of
ing across the width of the conveyor 17. After passage
under the head 30, the particles are picked up by means 25 the glass in the direction under the head 50. Vibration
of the head 50 is usuallyarranged to be in a direction
such as a suction tube 38 at the forward side of the third
generally parallel to the surface being polished but may
stage of the grinding-polishing operation. The horizontal
be vibrated in a direction perpendicular to the surface be
oscillation of the head 30 according to the con?gura
ing
treated, under which circumstances, if the head is ar
tions indicated above, provide somewhat of a wiping
ranged to overlap and su?iciently overhang such edge, such
action over the surface of the sheet 15 which causes the 30
as the edge of the sheet 55, it can be made to trim off the
glass surface to take on a smooth planar form. At
excess
portions while, at the same time, treating the edges
each successive stage of the three-stage operation, the
for the polishing operation. Under some circumstances,
abrasive particles introduced to the glass surface may be
however, it may be desirable to vibrate the head in a
progressively ?ner in each stage such that in the ?nal or
third stage, the abrasive material is extremely ?ne to 35 direction diagonally toward a corner of the sheet 55 to
provide horizontal components of force which will oper
provide a lapping action more than a grinding action.
ate on vertically oriented portions of the sheet 55 for
An abrasive material which may be used for these pur
a
more positive polish of the edge while still other con
poses is boron carbide. Other materials which may also
ditions
might dictate that the head he alternately oscil
be employed are aluminum oxide, silicon carbide and
lated along the edge of the sheet and diagonally there
similar materials.
40 against.
Figure 3 illustrates a type of working head 40 which
Figure 5 and Figure 6 illustrate two different but some
may be utilized in the ?rst stage of the polishing-grinding
what similar types of working heads 60 and 70, respec
operation which is shaped to assure a positive ?ow of
tively, having longitudinal groove~type cavities on their
abrasive ?uid to the under surface of the head. To
under
surfaces extending along the dimension transverse
facilitate such flow, the rearward ' position 41 of the
to the sheet glass being worked.
>
45
under surface is inclined downwardly along an arcuate
In
Figure
5,
the
head
60
is
actuated
by
members
63- con
line toward the central part of the head and blends into
nected to transducers, not shown, and has a groove-type
the more horizontal portion 42 at the forward part of
cavity 62 which extends along the length of the under
the head. The head is vibrated in a direction generally
side of the head 60. The cavity has a longitudinal tube
perpendicular to its under surfaces by transducers con
50 61 recessed in the upper portion thereof from which
nected to the head by way of members 43.
Flow of abrasive particles thereunder is effected by
abrasive particles in liquid suspension are fed to the under
side of the head as it is being vibrated. The tube 61 has
introducing them behind the head 4% by means such as
spaced apertures along its length su?iciently close to
the abrasive supply tube 11 of Figures 1 and 2, and the
each other to introduce the liquid suspended abrasive
forward advancement of the glass sheet on which the
particles uniformly along the under side of the head
abrasive particles are deposited carries them under the 55 across the width of the sheet to be treated.
rearward edge and causes a wedging of the particles be
The structural form of the head 70 illustrated by Figure
tween the head and the sheet surface as they approach
6 is somewhat similar to the head 60 of Figure 5 in that
the more ?at position 42. The vertical vibratory action
it is vibratably actuated by a series of members 73 con
of the head 49 then actuates the particles to drive them
60 nected to driving transducers, not shown, and has longi
against the sheet surface.
tudinal groove-type cavities 72 thereunder which extend
It should be noted that although adjustable pressure
along the length of the under side of the head. Each
means are illustrated for varying the pressure of the head
30 against the sheet 15 in the third stage of the grinding
of the groove-type cavities of this structure, however, in
stead of being supplied with abrasive particles from tubes
polishing operation, similar varying pressure means are
recessed within the cavities are supplied from a common
adaptable to incorporation in the ?rst and second stages 65 tubular channel 71 centrally located Within the interior
of the operation. In this respect, pressure-adjusting com
of the head 7% and'has connecting channels 75 extend
ing to the cavities to feed liquid suspended abrasive par
pression spring arrangements associated with set screws,
ticles thereto. A plurality of the connecting channels
although not shown, can be inserted between the tie-in
member 13 and the head 10 in the ?rst stage, as well 70 75 extend to each of the longitudinal cavities 72 and are
spaced from each other to provide an even distribution
as between the tie-in member 13 and the head structure
of abrasive particles along the length of each of the
20 in the second stage. The transducers 12, and 22, re
cavities.
spectively, are thus arranged to operate against compres
As the head 70 is vibrated in a vertical direction, the
sion springs which are adjustable to provide the surface
particles ?owing from the cavities are introduced under
of the sheet 15 and correspondingly to provide the 75
the ?at surfaces 74 at the rearward edge of each of the
2,949,707‘
7
cavities and are driven into the surface of the glass in
a manner similar to operation of the non-grooved heads.
The particles subjected to the forces of heads of this type,
however, are more free to be agitated and are more uni
formly distributed across the length and the width of
the under part of the head 74!. Thus, the e?iciency of
the working action of the head 70 on the surface of the
sheet to be treated is somewhat better than that under
heads having no supply cavity or only a single abrasive
supply cavity thereunder.
8
across the width of the head than the rearward ?at sur
face portion 105.
As the head 80 is rocked about its pivot members 92,
engagement of the surface of the sheet 85' is alternated
between the surfaces 104 and 105. The two surfaces are
joined by a relatively short arcuately contoured portion
107. While being rocked, it is desirable, however, that
the surface portions 104 and 105 each make contact with
the glass surface for a longer period of time than the
portion 107 in order to ‘work the glass surface 85 most
In both the heads of Figure 5 and Figure 6, the supply
of abrasive in liquid suspension can be suitably provided
effectively. This is accomplished by suitably connecting
portions of channels 71 in the second. Excesses or used
abrasives on the surface of the glass worked may be
removed by means similar to the suction tube arrange
portions 184 and 195 makes contact with the glass surface,
it is effective in producing a polishing action by reason of
the high rate of oscillation of the head 80 in a horizontal
direction. The flow of abrasives from channel 162 is
the arm 95 to the pulley 96 in such manner that the head
80 is rocked more rapidly during the time the head 30
from an external source connected by way of one or
is resting on the intermediate portion 107 on the under
more ?exible hoses or tubes to the ends of the tube
61 in the ?rst instance or to the ends or more central 15 surface of the head. Thus, as each of the ?at surface
ment exempli?ed in the schematic diagram of Figure 2.
Another arrangement whereby transducer-actuated 20 arranged to be constant so that abrasives exist under the
working heads may be utilized to surface treat or grind
and polish glass surfaces is illustrated in Figure 7. In
head 80 at all times regardless of which of the flat bottom
portions of the head, rearward or forward, is in engage
ment with the surface to be treated.
this arrangement a head 80 extending across the width of
Figure 10 is a schematic sidc-elevational view of a
a sheet advanced thereunder is oscillated at a high vibra
tory rate across the width of the sheet as it is rocked over 25 series of three transducer-actuated working heads for
treating two sides of a glass sheet simultaneously. The
the surface at a lower frequency rate. The longitudinal
grinding-polishing operation in this arrangement is effected
head 80 extending across the surface and width of the
in a manner similar to that of Figures 1 and 2 with the
vsheet 85 is supported and driven by a pair of slidable
exception that a pair of vibrating working heads on op~
members. 99 which extend through a pair of suspended
head support members 86 located on opposite sides of the 30 posite sides of the sheet 115 in each stage are vibrationally
actuated to effect a polishing thereof. In the ?rst stage,
conveyor 87 carrying the sheet 85. The two support
heads 110 actuated by suitable transducers not shown
members 86 each have a transducer 84 associated there
are vibrated in a vertical direction and are supplied with
with arranged for transverse horizontal oscillation of the
liquid-suspended abrasive particles from longitudinal
head 80. The members are suspended from, and arranged
to be rocked about, pivot members 92.‘ located above the 35 cavities 111 in the rearward edge of each of the heads.
, Subsequent to use, the abrasive particles in this stage are
sheet 85 by a motor 34.
removed by way of a suction tube 118 on the top surface,
The motor is connected to one of the members 86 by
‘whereas at the bottom surface the used abrasive is re
an eccentrically driven connecting arm 95 pivotably se
moved by a wiper 116 and dropped to a pan 119 located
cured to the bottom portion of the member 36. At the
end toward the motor 94, the arm 95 is connected ec— 40 below the working zone. In both instances the abrasive
material may be recirculated for reintroduction onto the
centrically to a driven pulley 96.
heads 110 by way of their respective supply cavities 111.
I Suspension of the members 86 from the pivot members
Abrasive-containing ?uid fed from the bottom head 110
is supplied under pressure to assure positive ?ow of the
grees of working of the surface of the sheet 85. Oscilla 45 abrasive between the head and bottom surface of the
sheet 115.
tion of the head 80 across the width of the sheet 35 is
The second stage of the grinding-polishing operation
effected at relatively high vibratory rates above 400 cycles
is again similar to that of the arrangement of Figures 1
a second, whereas the rocking action is effected at a slower
and 2 with the heads 120 being driven diagonally into
rate in the order of 100 cycles a second or less. The
the opposite surfaces of the sheet 115. ‘Fluid suspended
rocking action, however, is arranged to be sufficient in
abrasive particles are supplied to positions under the
rate that substantially all portions of the surface of the
heads by way of cavities 121. Abrasive used on the top
glass are engaged and in effect rubbed transversely under
surface is removed by a suction tube 128 subsequent to
the in?uence of the head 80. Abrasive ?uid is supplied
advancement under the head and the used abrasive in the
to the head 80 by tubular means such as a pair of hoses
Q7 connected from an abrasive supply source to open 55 bottom surface of the sheet is removed by a wiper 126 and
deposited in a pan 129. In the third stage the ?nal action
ings at the top of the head and leading to an internal
on the two surfaces of the glass are effected by horizon~
channel 102..
'
V
tally oscillated heads 130 which are also supplied with
Figure 8 and Figure 9 each show two different positions
abrasive particles in liquid suspension from grooves 131.
of the type of head SG‘Which may be used in the assembly
of apparatus of Figure 7. The under surface of the head 60 Again, the used abrasive on the top surface of the sheet is
removed by the suction tube 138 whereas used abrasive on
is composed of two adjacent substantially ?at portions 194
the bottom surface is removed by a wiper 136 and is
and 105 oriented at a slight angle to each other. The
deposited in the pan 139.
rearward flat surface portion 105 is provided with a
Although there has been described herein what are con
groove-type cavity 162 which extends along the length
92 is made adjustable to permit raising and lowering of
the head 89 to different levels for various selectable de
of the head 89 and is connected to the abrasive supply 65 sidered the preferred embodiments of the invention, vari
ous modi?cations will be apparent to those skilled in the
channel 101 extending through the interior of the head
in the manner similar to the arrangement of Figure 6.
In the head of Figures 8 and 9, however, the abrasive sup
art. ' For example, although the grinding-polishing in the
present description have been related, and are preferably
ply channel is connected with a cavity located toward
accomplished with the working heads vibrating at high
the rearward edge of the head 89 so that the particles 70 frequencies, it will be understood that the structure and
introduced therefrom will have a greater horizontal dis
operation in the various stages would also be effective at
tance of effectiveness before being released from in
?uence of the vibratory action of the head 89. The for
ward under portion of the head Wis providedwith a sub
low frequencies.
Still further, it will‘ be understood that the transducer
. arrangements herein disclosed may be modi?ed such as
stantially ?at surface portion 104 of greater dimension 75 by making the length of the transducer heads extending
2,949,707
across the width of sheets contacted only a portion of the
total width, and arranging for a sweeping oscillation
across the full Width of the sheet. It is, therefore, my de
sire that the appended claims shall cover all modi?cations
and arrangements which come within the scope and spirit
of my invention.
I claim:
1. The method of treating a sheet of glass and like ma
terial for a polish comprising advancing a sheet of glass
under an electromechanical tool member extending across 10
a surface of the sheet transverse to the direction of ad
vancement of the sheet and in contacting relationship
therewith, interposing between the tool member and the
sheet a liquid suspension of ?nely comminuted abrasive,
10
substantially non-yielding materials such as glass for a
polish comprising a longitudinal tool member extending
across the surface of a sheet of the material, means for
advancing the sheet under the tool member in a direction
transverse to the longitudinal orientation of said tool
member, electromechanical transducer means for vibrat
ing said tool member ultrasonically invdirections diag
onal to and transversely across the surface across which
it extends, and means for interposing a liquid suspension
of comminuted abrasive between said sheet surface and
said tool member, said electromechanical transducer
means being so constructed that when operated in its nor
mal intended manner, the relative Vibration between the
tool member and sheet surface is at an ultrasonic fre
oscillating said electromechanical tool member at an 15 quency such that with a small amplitude, the tool mem
ultrasonic frequency in a direction transverse to the direc
tion of advancement of said sheet, and simultaneously
oscillating said tool member against said surface at
relatively the same high frequency and small amplitude
ber drives the abrasive particles suspended in liquid under
2. The method of treating-a sheet of glass and like
material for a polish comprising continuously advancing
advancing the sheet under the tool member in a direction
transverse to the longitudinal orientation of said tool
the tool member against the sheet surface to remove
material from the surface.
6. Apparatus for treating a surface of a sheet of hard,
with a component of movement perpendicular to said sur' 20 substantially non-yielding materials such as glass for a
face such as will effect removal of material from said
polish comprising a longitudinal tool member extending
surface.
across the surface of a sheet of the material, means for
a sheet of glass under an electromechanical tool member 25 member, means for biasing said tool'member against said
extending across a surface of the sheet transverse to the
surface, electromechanical transducer means for vibrat
direction of advancement of the sheet, interposing be
ing said tool member ultrasonically in a direction parallel
to the general orientation of the sheet and direction of
of ?nely comminuted abrasive, oscillating said tool mem
advancement of the sheet, separate electromechanical
ber electromechanically at anultrasonic frequency in a 30 means for vibrating said member longitudinally across
tween the tool member and the sheet a liquid suspension
direction transverse to the direction of advancement of
said sheet, and simultaneously oscillating said tool mem
ber continuously at relatively the same high frequency
said sheet surface ultrasonically simultaneously with
vibration parallel to the direction of advancement of the
sheet, and means for interposing a liquid suspension of
and low amplitude against said surface in a direction
comminuted abrasive between said sheet surface and said
having components of motion parallel and diagonal to 35 tool member.
the direction of advancement of said sheet, at a relative
7. Apparatus for treating a surface of a sheet of hard,
frequency and amplitude from a ?xed level‘ above the
substantially non-yielding materials such as glass for a
bottom of said sheet to effect removal of material from
polish comprising a longitudinal tool member extending
said surface to a predetermined thickness of said sheet.
across the surface of a sheet of the material, means for
3. The method of treating a sheet of glass and like 4.0 continuously advancing the sheet under the tool member
material for a polish comprising continuously advancing
in a direction transverse to the longitudinal orientation
a sheet of glass under an electromechanical tool member
of said tool member, electromechanical means for oscil
extending across a surface of the sheet transverse to the
lating said tool member at a given ultrasonic frequency
direction of advancement of the sheet, interposing be
tween the tool member and the'sheet a liquid suspension
longitudinally across said sheet, means for rocking said
45 tool continuously at a relatively lower frequency against
of ?nely comminuted abrasive, oscillating said tool mem
said surface about a pivot spaced a perpendicular dis
ber electromechanically at an ultrasonic frequency in a
tance from said surface, and means for interposing a
direction transverse to the direction of advancement of
liquid suspension of comminuted abrasive between said
said sheet, and simultaneously rocking said tool member
sheet surface and said tool member.
continuously at a relatively lower frequency over said
8. A multiple stage arrangement of apparatus for treat
50
surface about a pivot point spaced from said surface in
ing surfaces of a sheet of hard, substantially non-yielding
a direction perpendicular to the surface.
materials such as glass for a polish comprising three lon~
4. Apparatus for treating a surface of a sheet of hard,
gitudinal tool members extending generally parallel to
substantially non-yielding materials such as glass for a
each other across the surface of a sheet of the material,
polish comprising a longitudinal tool member extending
means for continuously advancing the sheet under the
across the surface of a sheet of the material, means for 55 tool members in a direction transverse to their longitu
advancing the sheet under the tool member in a direction
dinal orientation, means for interposing a liquid suspen
transverse to the longitudinal orientation of said tool
sion of comminuted abrasive between said sheet surface
member, electromechanical transducer means for vibrat
and each of said tool members, electromechanical trans
ing said tool member ultrasonically in a direction perpen
ducer means associated with said tool members for ultra
dicular to the surface across which it extends, means for 60
sonic vibration of each against said surface, the ?rst one
interposing a liquid suspension of comminuted abrasive
of
such members being arranged for ultrasonic vibration
between said sheet surface and said ‘tool member, said
in a direction perpendicular to the surface, the following
transducer means being so constructed that when oper
of said members being arranged for ultrasonic vibration
ated in its normal intended manner, the relative vibration‘
between the tool member and sheet surface are at an 65 in a direction diagonal to the surface, while the remaining
ultrasonic frequency such that with a small amplitude, _ member is biased against said surface and arranged to be
ultrasonically vibrated in a direction parallel to the direc
the tool member drives the abrasive particles suspended
tion of advancement of the sheet.
in liquid under the tool member against the sheet surface,
9. A multiple stage arrangement of apparatus like that
and electromechanical means for oscillating said member 70
of claim 8 in which each of the electromechanical tool
longitudinally across said sheet surface at substantially
members is provided with means for oscillating the re
the same high frequency and small vamplitude simulta
neously with its vibration ultrasonically in the perpendic
ular direction.
5. Apparatus for treating a surface of a sheet of hard,
spective members ultrasonically longitudinally across said
sheet surface simultaneously with its vibration against
said surface.
,
10. Apparatus for treating a surface of a sheet of hard,
2,949,707
7
l1
a
'52
in a direction transverse to the longitudinal orientation of
substantially non-yielding materials such as glass for a
said tool member, electromechanical means for oscillating
said tool member at a given ultrasonic frequency longi
tudinally across said sheet, means for rocking said tool
continuously at a relatively lower frequency against said
surface about a pivot axis spaced a perpendicular dis
polish comprising a longitudinal tool member extending
across the surface of a sheet of the material, means for
advancing the sheet under the tool member in a direc
tion transverse to the longitudinal orientation of said tool
member, electromechanical transducer means for vibrat
ing said tool member transversely across said sheet as
Well as in a direction diagonal to the surface across which
it extends, said transducer means being effective to vi
tance from said surface and across said sheet, and means
for interposing a liquid suspension of comminuted abrasive
between said sheet surface and said tool member, said
brate said tool member at ultrasonic frequencies in both 10 tool member having a contoured surface comprising two
angularly related planar portions arranged to alternately
said directions, means for selectively ?xing the pressure
engage said sheet in intimate relationship as said tool
of said tool member against said sheet surface, and means
member is rocked, said means for interposing the abrasive
for interposing under pressure a liquid suspension of
‘comminuted abrasive between said sheet surface and said
tool member, said electromechanical transducer means
being so constructed that when operated in its normal in
tended manner, the relative vibration between the tool
between said head and sheet being located in the one of
' said planar portions closest to the side of said head from
member and sheet surface are at an ultrasonic frequency
which said sheet is advanced.
References Cited in the tile of this patent
such that with a small amplitude, the tool member drives
UNITED STATES PATENTS
the abrasive particles suspended in liquid under the tool 20
member against the sheet surface to remove material from
the surface‘
11. Apparatus for treating a surface of a sheet of hard,
substantially non~yielding materials such as glass for a
2,070,944
Hillix ______________ ___ Feb. 16, 1937
2,504,831
Griss _______________ .__ Apr. 18, 1950
2,580,716
2,662,350
2,736,144
Balamuth ____________ __ Jan. 1, 1952
Laverdisse ___________ __ Dec. 15, 1953
Thatcher _____________ __ Feb. 28, 1956
across the surface of a sheet of the material, means for
2,787,100
Peyches ______________ __ Apr. 2, 1957
continuously advancing the sheet under the tool member
2,854,795
McCown ____________ __ Oct. 7, 1958'
polish comprising a longitudinal tool member extending